Related Experiment Video
Updated: Nov 20, 2025
Real-Time Electrocardiogram Monitoring During Treadmill Training in Mice
Published on: May 5, 2022
Exercise Ventricular Rates, Cardiopulmonary Exercise Performance, and Mortality in Patients With Heart Failure With
Mohamed B Elshazly1,2,3, Bruce L Wilkoff1, Khaldoun Tarakji1
1Department of Cardiovascular Medicine, Heart and Vascular Institute, Cleveland Clinic (M.B.E., B.L.W., K.T., Y.W., E.D., W.J., O.W., L.C.).
Background:
In heart failure (HF) with sinus rhythm, resting and exercise heart rates correlate with exercise capacity and mortality. However, in HF with atrial fibrillation (AF), this correlation is unknown. Our aim is to investigate the association of resting and exercise ventricular rates (VRs) with exercise capacity and mortality in HF with AF.
Methods:
We identified 903 patients with HF and AF referred for cardiopulmonary stress testing. AF was defined as history of AF and AF during cardiopulmonary stress testing. We constructed multivariable models to evaluate the association of resting VR, peak exercise VR, VR reserve (peak VR-resting VR), and chronotropic index with (1) peak oxygen consumption (PVO2) ≤18 mL/kg per minute, (2) continuous PVO2, and (3) 10-year all-cause mortality.
Results:
Median (25th-75th percentile) age was 60 (52-67) years, left ventricular ejection fraction was 25 (15-50)%, and 76.1% were males. Patients with lower (quartile 1) compared with higher (quartile 4) peak VR, VR reserve, and chronotropic index were more likely to have PVO2 ≤18 mL/kg per min (adjusted odds ratio [95% CI]: 14.92 [8.07-27.58], 24.60 [12.36-48.98], and 22.31 [11.24-44.27], respectively), and higher all-cause mortality (adjusted hazard ratio [95% CI]: 2.56 [1.62-4.04], 2.29 [1.47-3.59], and 2.30 [1.51-3.49], respectively). For every 10 beats per minute increase in VR reserve, PVO2 increased by 1.05 mL/kg per minute (B-coefficient [95% CI]: 1.05 [0.94-1.15]) and mortality decreased by 12% (adjusted hazard ratio [95% CI]: 0.88 [0.83-0.94]). Resting VR was associated with PVO2 (B-coefficient [95% CI]: -0.46 [-0.70 to -0.23]) but not mortality (adjusted hazard ratio [95% CI]: 0.97 [0.88-1.06]).
Conclusions:
In patients with HF and AF, higher resting VR and lower peak exercise VR, VR reserve, and chronotropic index were all associated with worse peak exercise capacity, but only lower exercise VR parameters were associated with higher mortality. Dedicated studies are needed to gauge whether modulating exercise VR enhances exercise performance and outcomes.
More Related Videos
Related Concept Videos
01:20Exercise and Cardiovascular Response
Light to moderate physical activity initiates a series of interconnected responses in the body. The heart rate modestly increases in anticipation of the workout, followed by widespread vasodilation as oxygen consumption by skeletal muscles increases. This results in decreased peripheral resistance, increased capillary blood flow, and accelerated...
01:17Exercise and Cardiac Output
Sustained exercise increases the muscles' oxygen demand, which can be...
01:17Pathophysiology of Heart Failure
01:30Heart Failure V: Medical Management
01:19Cardiac Output I:Effect of Heart Rate on Cardiac Output
Cardiac output (CO) refers to the total amount of blood ejected by one of the ventricles in liters per minute (L/min). In a resting adult, CO ranges from 5 to 6 L/min, adjusting according to the body's metabolic requirements.
Effect of Heart Rate on Cardiac Output
Cardiac output adapts to metabolic demands during stress, physical activity, or illness. The autonomic nervous system regulates heart rate via the sinoatrial node. The parasympathetic nervous system decreases heart...
01:22Heart Failure VI: Adjunct Therapies